fix: Fix short error summary

[Pijukatel]

Description

• Wrap Timeout errors raised by user-defined handler by UserHandlerTimeoutError (Otherwise it would be misunderstood as Request handler timed out after 60 s)
• Ensure that get_one_line_error_summary_if_possible does not access a non-existing index

Issues

• Closes: TimeoutError from asyncio.wait_for is not handled gracefully and crashes Crawlee #1602

Testing

• Unit tests

Checklist

• CI passed

[Pijukatel]

Reported example would now log something like this

...
[crawlee.crawlers._basic._basic_crawler] WARN  Retrying request to https://a.placeholder.com due to: Timeout raised by user defined handler. File "...crawlee-python/tests/unit/crawlers/_basic/test_basic_crawler.py", line 1576, in default_handler,     await asyncio.wait_for(Future(), timeout=1)
[crawlee.crawlers._basic._basic_crawler] ERROR Request to https://a.placeholder.com failed and reached maximum retries
   File "...crawlee-python/src/crawlee/router.py", line 106, in __call__
    return await user_defined_handler(context)
  File "...crawlee-python/tests/unit/crawlers/_basic/test_basic_crawler.py", line 1576, in default_handler
    await asyncio.wait_for(Future(), timeout=1)
asyncio.exceptions.TimeoutError
...

[vdusek]

One comment, otherwise LGTM

[vdusek]

do we need to import this?

[Pijukatel]

Good catch. Only the first one is needed.